Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations carry only destructiveHint:true, so the description does the heavy lifting and does it well: it discloses a data-scope prohibition (no card/billing), server-side validation behavior (the site may require additional fields and Mindbody reports which), and a safe validation path (test:true commits nothing). This is real operational context, not restatement.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Three tight clauses, front-loaded with purpose and requirements, then constraints and dry-run guidance. No filler, and the Mindbody endpoint is a useful trailing detail.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a 21-parameter mutation with no output schema, the description covers the critical unknowns: required fields, extra server-side requirements, the disallowed data class, and dry-run support. It does not describe what a successful creation returns (e.g., new client ID), which is the main remaining gap.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so all 21 parameters are already documented in the schema. The description reinforces the required names and the test flag but adds no syntax, format, or edge-case detail beyond what the schema already says; baseline 3 applies.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource ('Create a new client record') and immediately bounds the scope by what data it will not take ('No card or billing data is accepted'), which cleanly separates it from mindbody_update_client and mindbody_add_client_to_class.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Gives concrete usage context: minimum required fields, the fact that the site may demand more, and how to dry-run via test:true. It stops short of explicitly naming an alternative tool or stating when not to use this one.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.